The population of Cambodia is rapidly aging. Life expectancy at birth has increased from 58 years in 1995 to 71 years in 2012 driving the rate of previously unknown non-communicable diseases (NCDs) skyward. Ischemic heart disease and stroke are now the top two causes of mortality in this low income country and rates of cardiovascular risk factors including hypertension and diabetes are dramatically increasing. While the Cambodian government has done little to address the growing burden of NCDs afflicting its people, a non- governmental organization (NGO), MoPoTsyo Patient Information Center, has stepped in. Using a model of community-based patient-led Peer Educator Networks, MoPoTsyo is currently delivering self-management training and medications to over 21,000 hypertensive and diabetic patients in Cambodia. In spite of the considerable success this model has demonstrated, control of these conditions - particularly hypertension among non-diabetics - remains a challenge. The primary aim of this application, in response to PAR-14-028, Mobile Health: Technology and Outcomes in Low and Middle Income Countries (R21), is to enhance the communication network between the MoPoTsyo patient database, Peer Educators, pharmacies, and patients, using mobile eHealth tools to activate better compliance with treatment guidelines. Specifically, we plan to 1) Finalize enhanced features of the mHealth communications application for self-management of hypertension and diabetes, and pilot test it with end-users for acceptability and ease of use; 2) Implement a randomized controlled clinical intervention to assess the mHealth communications application in rural and urban-poverty communities for reducing study outcomes related to diabetes and hypertension; and 3) Share results with the Cambodian Ministry of Health and development partners in order to inform health policy makers of study findings and to develop strategies for improving control of hypertension and diabetes throughout Cambodia. This e-health communication system using mobile phone technology will include (a) voice messaging in Khmer allowing illiterate users to participate; (b) interactive tailored reminders and messages to patients for improving support for treatment adherence and goal achievement; (c) integration of messages received and responses from users into the health care database to trigger new messages; (d) access to pharmacy data to monitor individual adherence to medication; (e) access of health care information to Peer Educators to improve monitoring of patients over time; and (f) use of the system to integrate data into the MoPoTsyo database for reports and surveillance of patients. Fifty Peer Educators representing over 6000 rural, sub-urban, and urban patients will be randomized to the intervention or control. Process outcomes and health indicators including control of blood pressure and glucose, medication adherence, and lifestyle factors such as smoking, body- mass index, diet and exercise, will be evaluated. Results will be used to help develop national health policies addressing the great need for NCD control in Cambodia and serve as a model of other countries in SE Asia.